All about alternator parts

3g kitWe have alternator kits, but what about alternator parts themselves?  Since, we do have alternator rebuild kits, it would be nice to know a little more detail about each of the parts that go in to building and alternator.  Alternators typically consist of front plate, back plate, stator, rectifier, rotor, front bearing, back bearing, pulley, and a regulator.  These are the main parts of an alternator.

The front and back plate of an alternator is used to enclose the alternator together.  With the through bolts properly installed you will have the two halves tightly secured.  Many times these are two aluminum castings, but sometimes the back plate is just a plastic cover or tin to pretty much cover up the back of the alternator.

statorThe stator is the alternator component that is stationary inside of the casing.  It’s purpose is to be the other half of the electrical power source.  They commonly have a 3 phase wire set up with laminated iron plates.  Then the wires connect to the rectifier.

rotorThe rotor is yet another major part of an alternator.  This is the other half of the electrical power source, only instead of remaining stationary, this part is rotating with engine RPM.  As the the rotor is turns it induces a current in the stator windings to be stored in the cars battery.

rectifierThe rectifier is an alternator part that converts the  alternating current into a direct current.  This way the electricity that is produced can be sent to your car battery the proper way.  The rectifiers has diodes that make this process possible.  This also allows the current to flow in one (and only one) direction.

pulleyThe alternator pulley is attached to the drive end of the rotor.  This allows the rotor to be hooked up to the engines belt also referred to as the serpentine/drive belt.  This makes a good way for your vehicle to run and charge itself at the same time.

The end bearing and drive bearing.  These are usually on both sides of the rotor to help the rotor turn freely.  The drive bearing is located on the same side as the pulley.  The end bearing is at the back of the alternator which is also on the end plate.

3g regulatorTime for the last main alternator part to be mentioned.  This is the regulator.  This part helps regulate the current that flows from the alternator to the battery.  This is in most alternators today, however you do still have alternators that are not equipped with a regulator.  In those cases the cars computer regulates the current that flows from the alternator to the cars battery.

This article was created for basic know how of the different alternator parts components of an alternator, and  what their purposes are, and where they are located on a typical alternator.  To some this will be common knowledge, but to others, there maybe a tid bit of material that is useful for a rebuild job.  Happy rebuilding!


↑ Back to Top